In order to understand complex brain functions, it is essential to measure the neural activity of multiple neurons simultaneously with cellular resolution from living animals. Imaging neural activity with genetically encoded indicators has been widely used to visualize neural activity. The research group led by Masayuki Sakamoto (Kyoto University), Masatoshi Inoue (Stanford University), and Haruhiko Bito (The University of Tokyo) has successfully developed transgenic mice that stably express a high-sensitive and fast calcium sensor, G-CaMP9a. In vivo imaging reveals spontaneous and sensory-evoked calcium transients in excitatory and inhibitory ensembles with cellular resolution. This result shows that a new transgenic line facilitates dissecting complex dynamics of neural networks in vivo.

The results were published in Cell Reports Methods on February 14, 2022.